Toxic Cyanobacteria

Cyanobacteria can grow on surfaces like rocks, sticks, and sand.

NPS

Capitol Reef National Park monitors for the presence of toxic cyanobacteria and cyanotoxins in water throughout the park. We share information so you can make informed decisions about whether and how to recreate. We work with the Utah Department of Environmental Quality to share recreational advisory levels for still and flowing water throughout the park. Recreational advisory levels are:

• Health Watch
• Warning
• Danger

Learn more about how the Utah Department of Environmental Quality sets these levels. The National Park Service shares current recreational advisory levels for Capitol Reef on this page.

Health Watch in Effect: Halls Creek is under a Health Watch for the presence of anatoxin-a. Levels are below the state threshold for a warning.

Need to know:

• Do not drink stream water from waterways under a health watch, warning, or danger. Carry water or filter directly from a spring.
• If a harmful algae mat is present, avoid touching or disturbing it and keep everyone away.
• Avoid swimming and submerging the head in areas with visible harmful algae mats.
• There currently are no backcountry filters proven to remove cyanotoxins. Things like UV light, iodine, boiling water, etc. do not help at all. Those processes release the toxins into the water.
• Toxins may be present in the water disconnected from visible growth but this is usually insignificant or low concentrations.